[Nazo]

Lately I've mostly been using my modded HD555s mostly with a CMOY amp for various reasons. By modded I mean that first I removed the surround reflector foam (effectively making them HD595s) and then I did the soundstage mod, making them a bit better. I've also recabled them temporarily with a leftover Mogami star quad cable (I mean to switch to Canare star quad later probably as it's a much nicer cable to deal with IMO and I never heard an extreme difference between the Mogami and the Canare anyway.) Considerations of what to get should probably be more based on the HD595 if there's any real difference in terms of Op-Amp matching. As such, I see no reason not to try to get whatever Op-Amp should work best for me with this thing (or at least reasonably close.)

One thing of note is that I'm coming from the modded Denon AH-D2000s which in many ways I felt were a bit too sibilant to the point of being outright painful on a rare few songs. I guess the Sennheiser sound just suits me better because I find myself listening with the HD555s far more often and enjoying them a lot more. As such, I don't want to change their sound too much. Specifically, I don't want any attempts to Op-Amp match to shift the frequencies such that they sound like the Denons did to me for instance. Still, that's not to say that if there were room for improvement I wouldn't welcome it. I should probably add here that I'm kind of not exactly rich atm so I can't afford anything ridiculous, but then most of the CMOY-compatible Op-Amps really aren't bank breaking after all so this is probably not an issue.

Currently I'm using the OPA2132PA which came with it. I don't have a brown-dog adapter handy, but of course it shouldn't be too hard to get one. If one is necessary, does anyone have any part numbers convenient or anything like that? I'd probably be getting whatever I'm looking at from Mouser unless anyone has any better suggestions of places to look? (Actually, what would be really nice is if there were a place where I could get both the OPAMP and the Canare cable from at the same time. The biggest thing holding me back from getting the cable already is how much shipping costs from the main site I'm using. If I could combine the two things into one and just pay shipping once it would really be nice and convenient. (Well, I realize there probably are no great sites for this, but I thought I'd ask while I was at it.)

EDIT: Oh, I almost forgot, but atm I'm fitting all of this into an Altoids tin. I don't have room to fit two 9V batteries or a series of AAAs or something, so right now I can't realistically use anything that has really high voltage requirements. I'm actually ordering a rechargeable 9V battery (well, they call them "9V" but it's NiMH and will be less probably -- I'm not sure from the discussions though atm and will just have to wait and see, but normally they seem to be 7.2V rather than 8.4 or 9.6, however this one might be at least 8.4 from what I'm seeing in one of the discussions -- maybe even 9.6 which would actually make them dangerous for some electronics, though a CMOY isn't going to mind at all I'm sure) which might be tricky with anything that's too picky. These headphones are pretty efficient and the non-rechargeable 9V I have seems to be doing fairly well even at well below that already right now on the OPA2132PA, so at least with it I know the rechargeable should last a pretty good while with a normal OPAMP like this. Short of putting the whole thing in a new case though, there's just no room for anything more, so a really hungry OPAMP would be kind of unreasonable atm.

 

[Nazo]

*Bump*

Did I post this in the wrong forum? I really was tempted to put it in headphones since it's about matching to certain headphone types, but then it is ultimately about the CMOY amp specifically. Has anyone tried different OPAMPs with these sorts of headphones at least and maybe can just comment on what sounded best to them at least?

 

[Nazo]

One more bump I guess. I can't afford to just try a bunch randomly unfortunately. I need to pick just one or two at the most ideally.

I did notice something interesting recently though. All of the 9V batteries I had on hand to put in my CMoy started dying (they were all cheap old things from various smoke detectors that had been in them for a long time probably -- and btw, one interesting thing of note was that they didn't start really clipping and such until they dropped well below 6V) so I had to use my iBasso D3 which I originally got for my Denons. With the Denons it sounded better than just about anything I'd tried, but with these HD555s it actually sounded far worse which is kind of sad given how expensive it was. Well, that may not be a coincidence as I recall feeling the CMoy was too bright with the Denons but the iBasso D3 suited them quite well. So maybe the OPA2132 is at least on the right path for the Sennheisers. I suspected as much from the start though. My only real question is: is there anything that's better or even the best suited for them for the CMoy?


BTW, I don't think I can buy any other amps right now, but does anyone know of good cheap amps that suit the Sennheisers well that are maybe better than the CMoy? In particular, I really need something else that's portable since this CMoy is kind of attached to my computer on a semi-permanent basis except for an emergency. What else among the cheaper portable amps suits the Sennheisers well? It doesn't have to be super-cheap as I'm only asking for the future rather than right this minute (eg I can maybe even consider something as much as, say, $50 or whatever) but I'll probably need to get one in a not so far off future.